IL2 and systemic lupus erythematosus: Lung inflammation is another symptom of pristane-induced lupus mice that manifests as perivascular macrophage, neutrophil and lymphocyte infiltration.50,51 Notably, perivascular infiltration of mononuclear cells in the lung was readily observed in control mice but not L72-FSY- or PEG-L72FSY-treated mice (Fig. 6a), indicating that FSY-incorporated IL-2 suppressed lung inflammation in pristane-treated mice.